The location is superb, very easy to get around. Both the MRT and BTS are just walking distance to the apartment, a great convenience especially for people wanting to go to places like Chatuchak, Four-face Buddha, MBK, Central World, Neon Night Market, Rot Fai Train Night Market, Siam Square etc.... Terminal 21 also provides a very convenient location to eat, shop and relax. Nearby also has a few massage centers, and even a Mcdonald's.
The owner also showed concern to my problems, especially during my journey from the Airport to the apartment on the first day. I was stuck in a very bad traffic jam (no fault of the owner), but still he was concerned enough to find alternatives for me as I was already stuck in the jam for 2-3hours.
In general, I had a good holiday, besides the traffic jams.